Food suppliers find it necessary to transport a range of food inventories from warehouses to stores or supermarkets. The food is transported in a "transport", such as a trailer or semi-trailer, which is pulled along a highway by truck or tractor. Supplying such food inventories to stores is more efficient when a substantial inventory is transported and delivered to each store at a time, rather than to transport certain food items, which form a part of an inventory, to each store on a delivery route and then returning to each store with other food items to complete the inventory of each store. The efficiency is enhanced by proper loading of the inventory for each store to allow for a minimum of time for unloading. This is usually accomplished by loading food items first that are to be taken off last. Loading and unloading thus proceeds according to the itinerary of the transport along its delivery route.
But while unloading an inventory at one store at a time has its efficiencies, it poses the problem of transporting differing food items that require differing temperature environments during transportation. In particular, food suppliers that furnish the range of food items, including ambient temperature foods, fresh produce, chilled produce and processed foods, and frozen foods, must transport the range of types of food products that require two, perhaps three different temperature environments during transporting. Under certain outside conditions, an outside ambient temperature might provide a desired temperature environment for fresh produce and other food stuffs, but may be too warm for certain foods requiring low but nonfreezing temperatures which preserve the desirable characteristics of perishable foods for reasonable periods of time. Still other foods must be frozen to keep for long periods of time and to markedly reduce ensymatic actions. Thus, the food transport for a range of inventory must have at least two, perhaps three compartments.
Concomitant with the problem of providing compartments for transporting foods at different temperatures is the problem of loading the foods for efficient unloading. Typically transports have a rear door and, if there are more than one temperature zones in the transport, one or two side doors. It is desirable that foods may be pulled from any available door at any one stop, so that the itinerary may be dictated by the proximity of stops rather than by which stops have back-in loading docks and so should be unloaded through a rear door and which stops must be unloaded curb-side and so should be unloaded through a side door.
Loading also poses other problems. It is customary to move produce or frozen foods out of the cooling chamber or freezer, and by fork lift, move the produce or frozen foods through ambient atmosphere into the refrigerated transport. Usually pallets support the produce or frozen foods for lifting and loading the produce or frozen foods. The pallets must be supported above the floor so that the forks of the fork lift may be slid underneath the pallet. Standard pallets have parallel runners or "skids" attached beneath to support the pallet above the floor. But standard pallets must usually be set upon the floor of the transport at the door of the transport, because the fork lift usually cannot be maneuvered into a substantially loaded truck. The pallets then must be pushed or slid across the floor with significant effort to overcome substantial resistance by friction. Of course, sliding pallets cause substantial wear to the floor of the transport.